The present invention relates generally to battery chargers and more specifically to a system and method for verifying that a USB port has sufficient power to charge a rechargeable battery at a predetermined source current level while maintaining a minimum specified output voltage.
USB ports are provided in most presently manufactured desktop and laptop computers and are commonly used to interface peripheral devices to such computers. Due to the ubiquitous nature of USB ports in a computing environment, it is desirable to utilize such ports as a power source for the charging of rechargeable batteries. However, prior to the coupling of the USB port to a rechargeable battery it is desirable to verify that the specific USB port being used has sufficient power that to charge the rechargeable battery while avoiding possible avoid damage that to USB port circuitry.
Other solutions to this problem rely on the USB controller to identify the USB type by a complex data evaluation process. It would therefore be desirable to have a simple, effective and reliable technique for verifying that the USB port to be utilized in the battery charging process has sufficient power prior to the initiation of charging.